Electrical loads in residential and industrial establishments tend to be reactive and not passive. The power factor of an alternating current (AC) electric power system is defined as being equal to the ratio of the real power to the apparent power of the load. The power factor is a number between zero and one and represents the efficiency of the load. In an electrical power system, a load with a low power factor draws more current than a load with a high power factor for the same amount of useful power transferred. Thus, it is desirable to have a load with a power factor as close as possible to unity. Due to the inductive nature of the majority of household appliances and machinery used in industrial applications, the power factor for these inductive loads is low. It is known in the art to add capacitance in parallel with the line input to raise the power factor to unity. As a result, savings in power consumption can be realized.
Currently in the market, power factor controllers are available which monitor the lead and lag in the power and automatically adjust the power factor by applying more or less capacitance as needed. However, power factor correction devices currently known in the art are designed to be installed at the electrical panel or alternatively they may be installed directly to each of the individual loads that require power factor correction. For a residential application, the factor power correction controller is usually connected to the fuse panel where the electricity is distributed to different locations within the house. As such, in order for the electrician to install the power factor correction controller, the electrician must have access to the residence and approval from the homeowner.
Utility companies are motivated to increase the power factor at each residence that they service because a power factor below one requires the utility to generate more than the minimum volt-amperes necessary to supply the real power (watts). A low power factor therefore increases generation and transmission costs for the utility company. However, the utility companies are deterred from installing residential power factor controllers because they must schedule the installation with the customer and they are concerned with possibility liability issues. Additionally, customers are reluctant to have a power factor controller installed due to the inconvenience associated with the installation inside their home.
Therefore, there exists a need in the art for a power factor controller that can be installed at an individual residence which does not require that the installer have access to the fuse panel inside the residence.